The present invention relates to an ultrasonic diagnostic apparatus.
The ultrasonic diagnostic apparatus is known to used for displaying tomographic images (B-mode images) of an inspection subject by using ultrasonic waves. The ultrasonic diagnostic apparatus, which is capable of readily producing tomographic images on a real-time basis, is used extensively in the medical field for the inspection of a fetus, a heart, etc.
The ultrasonic diagnostic apparatus has various operation modes including B mode, M mode, and D mode. The B mode is mainly used for tomographic imaging of stationary organs of the inspection subject. The M mode, which displays a sonic line of time-serial B-mode images, is used for viewing the motion of a moving part such as a valve of a heart. The D mode, which is based on the Doppler effect of ultrasonic waves reflected by a moving part which causes the echo frequency to shift in proportion to the velocity of movement, is used for measuring the blood flow speed and for imaging a blood stream.
The ultrasonic diagnostic apparatus includes a primary recording device called “cine memory”. The cine memory memorizes data of tomographic images of an inspection subject in the form of frames which have been produced consecutively by scanning (for example, refer to Patent Document 1.)
[Patent Document 1] Japanese Unexamined Patent Publication No. 2002-112254
The cine memory is a ring buffer memory having a small storage capacity and is capable of high-speed data writing. The memory stores produced image data of frames until it is full and thereafter stores image data of frames by overwriting the oldest frame with the newest frame sequentially.
After the stop of the scanning operation, image data stored in the cine memory is used for display, and can also be saved in a secondary recording device having a large storage capacity such as a HDD (Hard Disk Drive) unit. Incidentally, a removable medium may be used as the secondary recording device.
When outputting the image data from the cine memory to the HDD unit, not only the image data of the all frames stored in the cine memory can be outputted and saved, but also the image data of frames within an intended range can be saved. Since only a necessary range of frames is saved, unnecessary image data is not displayed at diagnosis of the inspection subject, therefore the diagnosis by the inspector can efficiently be performed. Further, since the image of the unnecessary frame is not stored in the HDD unit, a storage capacity of the HDD unit can be efficiently used.
Conventionally, the operator transfers frame images within a necessary range from the cine memory to the HDD unit by displaying frame images sequentially and setting the start point and end point of the frame range by fast feeding the frames forwardly and reversely many times with an operation device, such as a trackball device or the like.
Since the operator performs awkward operations such as fast feeding the frames forwardly and reversely repeatedly in order to set the necessary range, the operator has to bear a great burden, resulting in a low operational efficiency.